Lubricants Technical Publications
109. Test Device and Method for Evaluation of Lubricants for PM Compaction: A critical path to increase mechanical properties, especially fatigue strength, is to increase part density. A logical way to increase part density is to decrease the amount of admixed lubricant, decrease friction losses and compact at elevated temperature. A test device and test method was developed to permit the direct measurement of powder/die friction at temperatures up to 200ºC. Commercial and experimental lubricants (admixed and die-wall) were evaluated at several die temperatures and compaction pressures. The effect of die temperature on "stick" and "slide" friction values is used to demonstrate the method's effectiveness.
48. A Performance Comparison of Various PM Lubricants and Routes to Improvement: Greater demands are being placed on lubricant performance because of general industry trends toward more intricate part shapes with related tooling complexity and the incorporation of abrasive additives in mixes. To illustrate the significance of these performance demands, it is necessary to identify the role lubricants play in mixing and the PM part manufacturing process. This work examines the effects of lubricants on material flow, apparent density, compaction, ejection characteristics and sintered properties. The findings identify key performance elements, which provide a model for developing an improved PM lubricant. A performance comparison with a commercial lubricant highlights the advantages of a composite lubricant that was evaluated.